Effects of undercutting and sliding on calving: a global approach applied to Kronebreen, Svalbard
In this paper, we study the effects of basal friction, sub-aqueous undercutting and glacier geometry on the calving process by combining six different models in an offline-coupled workflow: a continuum–mechanical ice flow model (Elmer/Ice), a climatic mass balance model, a simple subglacial hydrolog...
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ftcopernicus:oai:publications.copernicus.org:tc60827 2023-05-15T16:22:10+02:00 Effects of undercutting and sliding on calving: a global approach applied to Kronebreen, Svalbard Vallot, Dorothée Åström, Jan Zwinger, Thomas Pettersson, Rickard Everett, Alistair Benn, Douglas I. Luckman, Adrian Pelt, Ward J. J. Nick, Faezeh Kohler, Jack 2019-01-18 application/pdf https://doi.org/10.5194/tc-12-609-2018 https://tc.copernicus.org/articles/12/609/2018/ eng eng doi:10.5194/tc-12-609-2018 https://tc.copernicus.org/articles/12/609/2018/ eISSN: 1994-0424 Text 2019 ftcopernicus https://doi.org/10.5194/tc-12-609-2018 2020-07-20T16:23:25Z In this paper, we study the effects of basal friction, sub-aqueous undercutting and glacier geometry on the calving process by combining six different models in an offline-coupled workflow: a continuum–mechanical ice flow model (Elmer/Ice), a climatic mass balance model, a simple subglacial hydrology model, a plume model, an undercutting model and a discrete particle model to investigate fracture dynamics (Helsinki Discrete Element Model, HiDEM). We demonstrate the feasibility of reproducing the observed calving retreat at the front of Kronebreen, a tidewater glacier in Svalbard, during a melt season by using the output from the first five models as input to HiDEM. Basal sliding and glacier motion are addressed using Elmer/Ice, while calving is modelled by HiDEM. A hydrology model calculates subglacial drainage paths and indicates two main outlets with different discharges. Depending on the discharge, the plume model computes frontal melt rates, which are iteratively projected to the actual front of the glacier at subglacial discharge locations. This produces undercutting of different sizes, as melt is concentrated close to the surface for high discharge and is more diffuse for low discharge. By testing different configurations, we show that undercutting plays a key role in glacier retreat and is necessary to reproduce observed retreat in the vicinity of the discharge locations during the melting season. Calving rates are also influenced by basal friction, through its effects on near-terminus strain rates and ice velocity. Text glacier Svalbard Tidewater Copernicus Publications: E-Journals Kronebreen ENVELOPE(13.333,13.333,78.833,78.833) Svalbard The Cryosphere 12 2 609 625 |
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Open Polar |
collection |
Copernicus Publications: E-Journals |
op_collection_id |
ftcopernicus |
language |
English |
description |
In this paper, we study the effects of basal friction, sub-aqueous undercutting and glacier geometry on the calving process by combining six different models in an offline-coupled workflow: a continuum–mechanical ice flow model (Elmer/Ice), a climatic mass balance model, a simple subglacial hydrology model, a plume model, an undercutting model and a discrete particle model to investigate fracture dynamics (Helsinki Discrete Element Model, HiDEM). We demonstrate the feasibility of reproducing the observed calving retreat at the front of Kronebreen, a tidewater glacier in Svalbard, during a melt season by using the output from the first five models as input to HiDEM. Basal sliding and glacier motion are addressed using Elmer/Ice, while calving is modelled by HiDEM. A hydrology model calculates subglacial drainage paths and indicates two main outlets with different discharges. Depending on the discharge, the plume model computes frontal melt rates, which are iteratively projected to the actual front of the glacier at subglacial discharge locations. This produces undercutting of different sizes, as melt is concentrated close to the surface for high discharge and is more diffuse for low discharge. By testing different configurations, we show that undercutting plays a key role in glacier retreat and is necessary to reproduce observed retreat in the vicinity of the discharge locations during the melting season. Calving rates are also influenced by basal friction, through its effects on near-terminus strain rates and ice velocity. |
format |
Text |
author |
Vallot, Dorothée Åström, Jan Zwinger, Thomas Pettersson, Rickard Everett, Alistair Benn, Douglas I. Luckman, Adrian Pelt, Ward J. J. Nick, Faezeh Kohler, Jack |
spellingShingle |
Vallot, Dorothée Åström, Jan Zwinger, Thomas Pettersson, Rickard Everett, Alistair Benn, Douglas I. Luckman, Adrian Pelt, Ward J. J. Nick, Faezeh Kohler, Jack Effects of undercutting and sliding on calving: a global approach applied to Kronebreen, Svalbard |
author_facet |
Vallot, Dorothée Åström, Jan Zwinger, Thomas Pettersson, Rickard Everett, Alistair Benn, Douglas I. Luckman, Adrian Pelt, Ward J. J. Nick, Faezeh Kohler, Jack |
author_sort |
Vallot, Dorothée |
title |
Effects of undercutting and sliding on calving: a global approach applied to Kronebreen, Svalbard |
title_short |
Effects of undercutting and sliding on calving: a global approach applied to Kronebreen, Svalbard |
title_full |
Effects of undercutting and sliding on calving: a global approach applied to Kronebreen, Svalbard |
title_fullStr |
Effects of undercutting and sliding on calving: a global approach applied to Kronebreen, Svalbard |
title_full_unstemmed |
Effects of undercutting and sliding on calving: a global approach applied to Kronebreen, Svalbard |
title_sort |
effects of undercutting and sliding on calving: a global approach applied to kronebreen, svalbard |
publishDate |
2019 |
url |
https://doi.org/10.5194/tc-12-609-2018 https://tc.copernicus.org/articles/12/609/2018/ |
long_lat |
ENVELOPE(13.333,13.333,78.833,78.833) |
geographic |
Kronebreen Svalbard |
geographic_facet |
Kronebreen Svalbard |
genre |
glacier Svalbard Tidewater |
genre_facet |
glacier Svalbard Tidewater |
op_source |
eISSN: 1994-0424 |
op_relation |
doi:10.5194/tc-12-609-2018 https://tc.copernicus.org/articles/12/609/2018/ |
op_doi |
https://doi.org/10.5194/tc-12-609-2018 |
container_title |
The Cryosphere |
container_volume |
12 |
container_issue |
2 |
container_start_page |
609 |
op_container_end_page |
625 |
_version_ |
1766010140834660352 |